Do 1-year outcomes predict 2-year outcomes for adult deformity surgery?

BACKGROUND CONTEXT

Health-related quality-of-life (HRQOL) measures are being used more frequently in the evaluation of the adult deformity patient. This is due in part to the validation of the deformity-specific Scolios Research Society-22 (SRS-22). Hence, relationships between HRQOL outcomes and traditional measures of success such as deformity correction, fusion healing, and complications are being established.

PURPOSE

To examine the pattern of HRQOL outcome responses after adult deformity surgery.

STUDY DESIGN

Analysis of prospective multicenter cohort.

PATIENT SAMPLE

Two hundred and eighty-three adult deformity patients with preoperative, 1-, and 2-year postoperative outcome measures.

OUTCOME MEASURES

SRS-22, Short Form-12 (SF-12), Oswestry Disability Index (ODI), and back and leg pain numeric rating scale scores.

METHODS

Preoperative versus postoperative health status measures were evaluated by matched-pairs sample t test statistics and post hoc analysis of variance (ANOVA) findings.

RESULTS

SRS-22 improved from a mean 3.03 points at baseline to 3.21 points at 6 months, 3.71 points at 1 year, and 3.70 points at 2 years post-op. Mean ODI score was 37.0 points pre-op and improved to 27.0 points at 6 months, and 22.8 points at 1 and 2 years post-op. Mean SF-12 physical component score was 33.7 points at baseline, improving to 36.9 points at 6 months, 40.6 points at 1 year, and 40.5 points at 2 years post-op. Paired samples analysis comparing 6-month and 1-year post-op scores showed deterioration for numeric rating scale leg pain (p=0.05). There was a trend for improvement in SF-12 physical component score (p=0.06). Significant improvement between 6 months and 1 year post-op was noted for ODI (p=0.02) and SRS total score (p<0.0001). Comparison of 1- versus 2-year postoperative scores revealed no statistically significant differences for any of the HRQOL parameters.

CONCLUSIONS

This study supports the application of HRQOL measures, including the deformity-specific SRS-22, as a valuable tool in the assessment of adult deformity patients. Change in outcome score stabilized after the 1-year postoperative interval, for most patients.